Well, I have another octo, I asked for a small one and the LFS derived. Its head is about the size of a thumb and the tentacles are about five inches in length. It has two blue spots on each side of its head. I put in the larger tank with my spiny and Valentini puffers, naso tang and the frogfish. The puffers both took a quick look the octo changed a few colors and the puffers went about there business. Well, any advice with feeding the little guy would be great or what species he might be.